Carrier guidance in elbows and switches of pneumatic tube systems



Oct. 4, 1955 R. HABERKORN ET AL 2,719,681

CARRIER GUIDANCE IN ELBOWS AND SWITCHES OF PNEUMATIC TUBE SYSTEMS Filed May 17, 1952 2 Sheets-Sheet l INVENTORS R. HABERKORN- A. ZIEGLER AT ORNEY x Oct. 4, 1955 R. HABERKORN ET AL 2,719,681

CARRIER GUIDANCE IN ELBOWS AND SWITCHES OF PNEUMATIC TUBE SYSTEMS Filed May 17, 1952 2 Sheets-Sheet 2 Fig.4-

1N VENTORS R. HABERKORN- v A. ZIEGLER ATTORNEY United States Patent CARRIER GUIDANCE 1N ELBOWSAND SWITCHES OF PNEUMATIC SYSTEMS Rudolf Haberkorn, Berlin-I chterfelde, and Alfred Ziegler, Stuttgart, Baden-Wurttemlierg, Gen'nany, assignors to lnternationalstandard Electric Corporation, New York, N. Y., a corporation of Delaware Application May 17, 1952, Serial No. 288,496 Claims priority, application Germany May 17, 1951 2 Claims. (Cl. 243--31) system of smaller curvature than would otherwise be necessary so as to prevent binding of the carrier at the curved region of the tube.

A feature of the invention relates to a curved or elbow tubular construction for pneumatic tube transporting systems whereby the abiilty of a carrier to negotiate a change in direction without binding is materially increased without correspondingly increasing the radius of curvature of the elbow or curve.

Another feature relates to a switching curve or elbow for pneumatic tube transport systems, wherein the elbow region is provided with a switch accommodating chamber and also with specially designed bulges at the entrance and exit ends of the switch chamber to reduce the space requirements for the curve or elbow section without introducing the likelihood of the carrier binding in the system.

A further feature relates to improvements in the elbow and directional switching structures of pneumatic tube systems generally.

Other features and advantages will appear from the following detail descriptions and the appended claims.

The invention will be described in connection with a preferred form, as illustrated in the attached drawing wherein Fig. l is a perspective view of the two symmetrical shell sections of a tube switch designed in accordance with the invention,

Fig. 2 is a sectional view of Fig. 4 taken along the line XY thereof.

Figs. 3 and 4 are additional explanatory views showing the location of the carrier in the two switching conditions.

The tube switch of Fig. 1 consists of two shells 3 and 4. In the shell section 3 there is supported a switching blade 5 having an upper surface 5a and a lower surface 5b, and which is pivotally mounted for example at the point so that the said blade can assume either the normal or downward position shown in Figs. 1 and 3 or the switched or upward position shown in Fig. 4. When the blade 5 is in the normal position the carrier can proceed in a straight line direction through the system in the direction of the arrow (Fig. 3). When the blade 5 is actuated it guides the carrier in a curved direction (Fig. 4). In order to accommodate the switch in its actuated position the shells 3 and 4 are provided with corresponding chambers 8. In accordance with the invention the tube formed of the shells 3 and 4 is expanded at the top of the tube just before the entrance end of chamber 8 to provide a chan- 2 nel-Iike vbulge 6. A pair of similar bulge sections 7. are provided on the bottom 'of the sections 3 and 4, these bulge sections 7 being curved downwardly from the straight portion of the sections 3-4. Thus, as shown in Fig. 3, the carrier entering the system in the direction of the arrow is guided at these bulges first by rounded edges 1, 2 of the tubular wall and later by surface 5a of blade 5 as the carrier advances through the switch. If desired, separate insertedor laid-in round bar's 2A may be fastened to these walls so as to guide the carrier along four points of its circumference prior to its contact with the switch blade 5. When the carrier is to be diverted downwardly through the curved section of the system it is guided by two of these rounded edges 2 or laid-in rods 2A which engage the bottom of the carrier, as shown in Figs. 2 and 4, while surface 5b of the blade 5 provides a third guide. Each of the tubular sections may be provided with an integral flange 9 so that when the two sections 3 and 4 are assembled together, the flanges 9 can be attached to the remaining part of the tubular system (not shown).

Fig. 2 shows a schematic cross-section of the assembled sections 3 and 4 taken along the line XY of Fig. 4. The chamber 7 is the channel-like bulge provided at the bottom of the tubular guide in accordance with the invention. The space above the switch blade 5 is the switch blade chamber 8. The carrier 11 is represented diagrammatically as three concentric circles in Fig. 2, the outer circle corresponding to the periphery of the carrier felt 11a, one of which is located at each end of the carrier. The carrier 11 is guided at three points whereby either the said rounded-out edges or round bars indicated at 2A in Fig. 2 and surface 5b of the switch blade 5 serve as guides. The height and width of the chamber 7 are interrelated in a certain ratio depending upon the diameter difference between the carrier felts and the body of the carrier itself.

When the carrier 11 proceeds along a certain are along the rounded-out edges or circular bars, the lower portion of the front and rear circular felts each will bear at two points and the upper portion of felts 11a will bear against surface 5b of the switch blade 5. The body proper of the carrier forms therewith the chord of the curvature of the arc of the tube to be passed by the carrier, that is the body of the carrier may extend into the free space between the rounded-out guiding edges or round guiding bars as is shown in Fig. 2. By this arrangement, the body of the carrier between the felts remains unaffected and is thus safe from damage while a curve of relatively small radius may be negotiated. In order to insure a smooth gliding of the carrier from the guiding edges 2 into the tube, the flat or floor surface is joined with the guiding edges at a suitable point to provide in effect a continuously smooth guiding arc for the carrier between the straight and curved portions of the system. By making the switching section out of two longitudinally split electrical shells, it is possible to take the section apart at any time to examine the switch member.

Various changes and modifications may be made in the embodiment as disclosed without departing from the spirit and scope of the invention.

What is claimed is:

1. A pneumatic carrier transport system for a carrier having circular end portions joined by a body portion of a given axial length and of a diameter less than the diameter of said end portions, a tubular guide for said carrier having an inside diameter approximately equal to the diameter of said end portions whereby said carrier is adapted to travel through said tube, a curved tube section coupled to said guide for changing the direction of travel of said carrier, said curved tube section characterized in that there is provided therein a plurality of spaced track elements to provide a way for said end portions, the spacing between said elements being less than the diameter of said end portions and greater than the diameter of said body portion, whereby a part of said body portion may travel between said elements without contacting same and thereby permitting the curvature of said curved portion to be of small radius relative to the axial length of said carrier.

2. A pneumatic carrier transport system as claimed in claim 1, wherein said curved tube section includes a pair of oppositely located outwardly extending bulge portions defining a pair of recesses in communication with said tubular guide and said'curved tube section, a shiftable switching member within said tube section adapted to fit within a first of said recesses, said track elements situated at the region of connection of one of said bulge portions with said tube section, a part of said body portion adapted to travel within the other of'said recesses.

References Cited in the file of this patent UNITED STATES PATENTS 398,836 Lieb Mar. 5, 1889 489,931 Clay Jan. 17, 1893 623,969 Batcheller May 2, 1899 686,680 Pearsall Nov. 12, 1901 

